(8) Converting dictionary managed temporary tablespace
is not supported as of Oracle 8.1.7

SQL> exec dbms_space_admin.tablespace_migrate_to_local('TEMPTM');
BEGIN dbms_space_admin.tablespace_migrate_to_local('TEMPTM'); END;
*
ERROR at line 1:
ORA-03245: Tablespace has to be dictionary managed, online and permanent to be able to migrate
ORA-06512: at "SYS.DBMS_SPACE_ADMIN", line 0
ORA-06512: at line 1

(9) Storage parameters do not play a role in UNIFORM
and SYSTEM LMTs as extents are handled at tablespace level.

Notes

1. To move an existing DMT to LMT without losing any
of the LMT features, you may consider creating a new LMT and then moving the
objects from the existing DMT to it. This way both uniform extent allocation
and local management of extents features are available.

2. As of Oracle 8.1.7, SYSTEM tablespace cannot be
Dictionary managed. It is supported in higher releases.

3. SMON Process coalesces only DMT tablespaces every
5 minutes, where pctincrease is not set to 0.

4. As of Oracle 8.1.5, it is possible to create LMTs
but not possible to migrate an existing DMT to LMT.

5. As of Oracle 8.1.6, it is possible to create and
migrate to LMT.

6. Tablespaces are by default created as LMTs in
Oracle 9i,

7. SYSTEM tablespace restrictions as LMT.

Creating or migrating the SYSTEM to LMT is a no
return process. Make sure that all the existing DMTs are first converted to LMT
before converting SYSTEM tablespace. If any DMT is present in the database
after conversion of the SYSTEM to LMT, then it will be marked as READ-ONLY and
it cannot be changed to READ-WRITE. The SYSTEM once created or converted to LMT
cannot be converted back to DMT. Once the SYSTEM is LMT no more DMTs can be
created in the database.

8. Once all the tablespaces are converted to LMTs,
the table FET$ would not contain any more records.

Conclusion

LMT is highly beneficial and powerful feature. The
management of object extents will become much easier. With implementation of LMTs,
one should re-evaluate and revise the extent management and object sizing
policies that were followed for DMTs.